The body of Kester David, who lived in Russell Avenue, was found under a railway arch in Palmers Green on July 7, 2010, a day after his 53rd birthday.

Enfield Police’s investigation at the time concluded that his death was non-suspicious, following a post-mortem examination which found Mr David died from burns and inhalation of fumes.

An inquest at Barnet Coroner’s Court on January 31, 2011 recorded an open verdict.

But his family say he was working as a police informant at the time, and the Metropolitan Police’s own internal reviews of the case revealed a number of errors in the original investigation - leading to an announcement last week that its murder squad would begin a new investigation.

In the wake of last Wednesday’s decision to reinvestigate, Roger David-Griffith, Mr David’s brother, told the Journal: “We are fighting for justice.

“What we are conscious of is that senior members of the police were aware last September that things weren’t as they should have been but it’s taken until April before they’ve come out and said ‘we are going to do a murder investigation’.”

Earlier this month, Mr David’s family began a civil action against the Met over their handling of the case, insisting that there was third party involvement and that the former bus driver did not take his own life.

Before he died, the family believe Mr David was working as a police informant.

Mr David-Griffith explained: “Some detail that came to light after Kester’s death suggests he had correspondence with the police shortly before he died.

“We do believe that someone got him because of whatever he was doing with the police.”

Mr David-Griffith said his brother was a “very likeable chap” who “didn’t have any enemies” and was not depressed.

Dismissing the theory Mr David committed suicide, he said: “It was his birthday on July 6 and he was supposed to meet up with me for my birthday on July 10 so we could celebrate it together.

“He was in really good spirits – you have to be really deranged and mentally gone to pour a can of petrol over yourself and set yourself alight.”

Two reviews into the original Enfield Police investigation, carried out by senior officers from the force last September and January, revealed errors which included officers not checking CCTV footage and failing to cross-reference DNA from the scene.

Mr David-Griffith accused Enfield Police of not doing “any investigation whatsoever”, blaming the force for neglecting Mr David’s case because of his race.

It is the latest in a string of cases to come to light recently accusing the Met of racism.

Ken Hinds, 52, chairman of Haringey Stop and Search Monitoring Group, said Met Commissioner Bernard Hogan-Howe “needs to root out the bad apples” in his force to restore the public’s faith.

He added: “He’s got to understand that this is a particular culture in the police that has been allowed to go on for far too long – a lot of the senior officers were around in the 1980s when it was alright to have racist banter.

“We need a better police force that is more representative of our community.”

A Met Police spokesman said the results of the internal reviews “remain under consideration” and detectives from the Homicide and Serious Crime Command “retain an open mind about the circumstances of Mr David’s death”.

He added: “The previous reviews found no evidence of racism. The death is being treated as unexplained at this stage.”

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